<template>
  <li>
    <label>
      <input
        type="checkbox"
        :checked="todo.done"
        @change="handleCheck(todo.id)"
      />
      <!-- 如下代码也能实现功能，但是不太推荐，因为有点违反原则，因为修改了props -->
      <!-- <input type="checkbox" v-model="todo.done"/> -->
      <span v-show="!todo.isEdit">{{todo.title}}</span>
      <input
        type="text"
        v-show="todo.isEdit"
        :value="todo.title"
        @blur="handleBlur(todo,$event)"
        ref="inputTitle"
      >
    </label>
    <button
      class="btn btn-danger"
      @click="handleDelete(todo.id)"
    >删除</button>
    <button
      v-show="!todo.isEdit"
      class="btn btn-edit"
      @click="handleEdit(todo)"
    >编辑</button>
  </li>
</template>

<script>
import pubsub from 'pubsub-js'
export default {
  name: 'MyItem',
  //声明接收todo对象
  props: ['todo'],
  methods: {
    //勾选or取消勾选
    handleCheck (id) {
      //通知App组件将对应的todo对象的done值取反
      this.$bus.$emit('checkTodo', id)
    },
    //删除
    handleDelete (id) {
      if (confirm('确定删除吗?')) {
        //this.$bus.$emit('deleteTodo',id)
        pubsub.publish('deleteTodo', id)
      }
    },
    //编辑
    handleEdit (todo) {
      //判断todo身上有没有isEdit这个属性
      // eslint-disable-next-line no-prototype-builtins
      if (todo.hasOwnProperty('isEdit')) {
        todo.isEdit = true
      } else {
        //console.log('@');
        this.$set(todo, 'isEdit', true)
      }
      this.$nextTick(function () {
        this.$refs.inputTitle.focus()
      })
    },
    //失去焦点回调(真正执行修改逻辑)
    handleBlur (todo, e) {
      todo.isEdit = false
      if (!e.target.value.trim()) return alert('输入不能为空')
      this.$bus.$emit('updateTodo', todo.id, e.target.value)
    }
  },
}
</script>

<style scoped>
/*item*/
li {
  list-style: none;
  height: 36px;
  line-height: 36px;
  padding: 0 5px;
  border-bottom: 1px solid #ddd;
}

li label {
  float: left;
  cursor: pointer;
}

li label li input {
  vertical-align: middle;
  margin-right: 6px;
  position: relative;
  top: -1px;
}

li button {
  float: right;
  display: none;
  margin-top: 3px;
}

li:before {
  content: initial;
}

li:last-child {
  border-bottom: none;
}

li:hover {
  background-color: #ddd;
}

li:hover button {
  display: block;
}
</style>